There is known a hermetic compressor which belongs to this class of fluid machine and which comprises an electric motor and a compressing mechanism arranged in a hermetic container such that drive power is transmitted from the electric motor to the compressing mechanism to compress a refrigerant.
Patent document 1 discloses a hermetic container composed of three members: a center, a top and a bottom shells, the center shell being a tubular member open at each end, and the top and bottom shells being cup-shaped members welded to each open end of the center shell, wherein welding of the shells are performed while applying a force to pools of molten metal in a weld area, in the direction in which welding progresses.